Or at least [Squonk42] couldn’t. In Sept. 2013, [Squonk42] posted up on the Arduino forums requesting the schematics and editable design files for the Arduino Yun, and he still hasn’t received them or even a response.

[Squonk42]’s hypothesis is that Arduino must have done what any “sane” engineer would do in this case when presented with a super-complex piece of hardware and a potentially tricky radio layout: just use the reference design (Atheros AP-121). That’s what everyone else in the industry did. And that’s smart, only the rest of the consumer electronics industry isn’t claiming to be Open Source Hardware while the reference design is protected by an NDA.

Is this a change of strategy for the Arduino folks or did they just make a mistake? We won’t know until they respond, and that answer’s a year and a half in coming. Let’s see what we can do about that. And who knows, maybe Arduino can lean on Atheros to open up their reference design? It’s already an open secret at best.

But before you go out lighting up your righteous Open Source Hardware pitchforks and sharpening up your torches, read through [Squonk42]’s case and then dig through the primary sources that he’s linked to make up your own mind. You’ll make your case more eloquently if you’re making it yourself.

Good luck, [Squonk42]! We hope you at least get your answer. Even if you already know it.

[Kevin] recently scored a Morse code keyer/sounder unit from the 1920s on eBay. While many hams would love to use an old keyer for CW, [Kevin] took a different route and repurposed it into a wireless web-connected morse code keyer.

[Kevin] mounted an Arduino Yun under the keyer, which listens for user input and provides web connectivity. The Yun connects to [Kevin]’s open-source web API he calls “morsel,” which allows it to send and receive messages with other morsel users. When a message is keyed in, the Yun publishes it to the API. When another keyer queries the API for incoming messages, the Yun downloads the morse sequence and replays it on the sounder.

[Kevin] also added some copper electrodes to the top of his enclosure, which act as capacitive buttons while keeping the keyer’s old-school appearance. The left button replays the most recently received message, and the right button sets the playback speed. Check out the video after the break to hear and see the keyer in action.

Keeping up with a kickstarter campaign can be quite a task, especially if your project is real (looking at you, Scribble Pen!) and you’re trying to keep up with product fabrication and all the other logistics involved in bringing a product to market. [macetech] are currently in the middle of a campaign themselves and built a loud, bright alert system to notify them of any new kickstarter backers.

The project uses a LED marquee to display the current number of backers, but every time a new backer contributes to the project, a blindingly bright green arrow traffic signal is illuminated and a piezo speaker plays a celebration tune. All of these devices are controlled by an Arduino Yun which, with its built-in Atheros chipset, easily connects to the network and monitors the kickstarter page for changes.

[macetech] used some interesting hardware to get everything to work together. They used a USB-to-RS232 cable with and FTDI chip to drive the LED marquee and a PowerSwitchTail 2 from Adafruit to drive the power-hungry traffic signal. Everything was put together in a presentable way for their workshop and works great! All of the source code is available on their project page, and you can check out their RGB LED Shades kickstarter campaign too.

A few years ago, the most common method to put an Arduino project on the web was to add a small router loaded up with OpenWrt, wire up a serial connection, and use this router as a bridge to the Internet. This odd arrangement was possibly because the existing Arduino Ethernet and WiFi shields were too expensive or not capable enough, but either way the Arduino crew took notice and released the Arduino Yun: an Arduino with an SoC running Linux with an Ethernet port. It’s pretty much the same thing as an Arduino wired up to a router, with the added bonus of having tons of libraries available.

Since the Yun is basically a SoC grafted onto an Arduino, we’re surprised we haven’t seen something like this before. It’s an Arduino shield that adds a Linux SoC, WiFi, Ethernet, and USB Host to any Arduino board from the Uno, to the Duemilanove and Mega. It is basically identical to the Arduino Yun, and like the Yun it’s completely open for anyone to remix, share, and reuse.

The Yun shield found on the Dragino website features a small SoC running OpenWrt, separated from the rest of the Arduino board with a serial connection. The Linux side of the stack features a 400MHz AR9331 (the same processor as the Yun), 16 MB of Flash, and 64 MB of RAM for running a built-in web server and sending all the sensor data an Arduino can gather up to the cloud (Yun, by the way, means cloud).

[Joakim] has built a clock that spells out the time in words. Wait a second – word clock, what is this, 2009? Word clocks are one of those projects that have become timeless. When we see a build that stands out, we make sure to write it up. [Joakim’s] clock is special for a number of reasons. The time is spelled out in Norwegian, and since the clock is a birthday gift for [Daniel], [Joakim] added the his full name to the clock’s repertoire.

One of the hard parts of word clock design is controlling light spill. [Joakim] used a simple 3D printed frame to box each LED in. This keeps the spill under control and makes everything easier to read. The RGB LED’s [Joakim] used are also a bit different from the norm. Rather than the WS2812 Neopixel, [Joakim] used LPD8806 LED strips. On the controller side [Joakim] may have gone a bit overboard in his choice of an Arduino Yun, but he does put the ATmega328 and Embedded Linux machine to good use.

The real magic happens at boot. [Daniel’s] name lights up in red, with various letters going green as each step completes. A green ‘D’ indicates an IP address was obtained from the router’s DHCP server. ‘N’ switches to green when four NTP servers have been contacted, and the Linux processor is reasonably sure it has the correct time. The last letter to change will be the ‘E’, which reports ambient light.

[Joakim] added a web interface to trigger his new features, such as a rainbow color palette, or the ability to show minutes by changing the color of the letters K,L,O,K. The final result is a slick package, which definitely brings a 2009 era design up to 2014 standards!

The Arduino Yún was the first of a new breed of Arduinos that added a big honkin’ Linux System on Chip to the familiar ATMega microcontroller and unique pin headers. It’s a surprisingly powerful system, but also very simple: basically, it’s just an Atheros AR9331 running Linux, an ATMega32u4 doing its Arduino thing, both connected by a serial connection. The Atheros AR9931 is also found in a router popular amongst hardware hackers. It really was only a matter of time before someone ported the Yun software to a router, then.

[Tony] took a TL-WR703N router and put OpenWRT on it. Turning this router into the Linux side of a Yún was a simple matter of uploading the Yún software to the root directory of the router and rebooting it. The Arduino side of the Yún is handled by an Arduino Mega connected to the USB port of the router. A quick update to Arduino’s boards.txt file, and a hacked together Yún is just a strip of duct tape away.

The Yún may not be extremely popular, but it does have a few interesting use cases. Maybe not enough to drop $70 on a board, but if you already have a WR703 router, this is a great way to experiment.

For the longest time, the creators of the Arduino have been looking at how to bring the Arduino platform into the cloud. Ethernet and WiFi shields technically work, but if you’re processing data scraped from a web page, a lowly microcontroller really isn’t the best option. Enter the Arduino YUN. At its core, it’s a regular old Arduino Leonardo. Underneath that metal plate on the board? That’s an SoC running Linux.

Basically, the Linux side of the Yun is pretty similar to a WiFi router running OpenWRT. There’s a USB port for plugging in peripherals, native WiFi support (802.11n, even!), an Ethernet connector, and enough RAM to do all the interesting stuff a small computer connected to the Internet can do.

To make all this web programming easier for Arduino neophytes, the YUN also includes a ‘bridge’ library that automates HTTP transactions between the Linux and microcontroller sides of the YUN. There’s also support for Temboo, an SDK for dozens of APIs that interact with Facebook, Dropbox, FedEx, and hundreds of other web services.

Below you can check out [Massimo] and [David] showing off their wares and going over how the YUN connects to the Internet and interacts with the microcontroller over the ‘bridge’. It’s an interesting device, and something we’ll surely check out at the World Maker Faire.